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• We present a discrete optimal control problem of glycerol fed-batch culture considering limited number of switches. • The problem is approximately transformed into two subproblems via time-scaling transformation and CIA decomposition. • We develop a fruit fly optimizer with modified sine cosine and adaptive maximum dwell rounding to solve the subproblems. • Numerical experiments are conducted to show the rationality, effectiveness and applicability of the approach proposed. This paper focuses on binary optimal control of fed-batch fermentation of glycerol by Klebsiella pneumoniae with pH feedback considering limited number of switches. To maximize the concentration of 1,3-propanediol at terminal time, we propose a binary optimal control problem subjected to time-coupled combinatorial constraint with the ratio of feeding rate of glycerol to that of NaOH as control variables. Based on time-scaling transformation and discretization, the binary optimal control problem is first transformed into a mixed binary parameter optimization problem consisting of not only continuous variables but also binary variables, which is then divided into two subproblems via combinatorial integral approximation decomposition. Finally, a novel fruit fly optimizer with modified sine cosine algorithm and adaptive maximum dwell rounding are applied to solve the obtained subproblems numerically. Numerical results show the rationality and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Objective. Colistin is an antibiotic of last resort for treating serious Gram-negative bacterial infections. However, the misuse of colistin, especially as an animal growth promoter, has contributed to increasing antimicrobial resistance, mediated mainly through plasmid transfer of the mcr-1 gene. This study assessed the prevalence of phenotypic and molecular colistin resistance in Escherichia coli and Klebsiella pneumoniae in Ecuador in healthy humans and their chickens and pigs. Methods. Fecal samples were collected from humans and their chickens and pigs in two rural coastal and Amazon regions between April and August 2020. Gram-negative bacteria were isolated and identified using conventional techniques. Phenotypic resistance was determined using the broth microdilution technique, and the mcr-1 gene was detected using conventional polymerase chain reaction. Results. A total of 438 fecal samples were obtained from 137 humans, 147 pigs and 154 chickens. The prevalence of E. coli isolates was 86.3% (378/438) and K. pneumoniae, 37.4% (164/438). Overall, the mcr-1 gene was found in 90% (340/378) of E. coli isolates, with higher prevalences found in isolates from coastal regions (96.5%, 191/198), humans (95.6%, 111/116) and chickens (91.8%, 123/134); for K. pneumoniae, the gene was found in 19.5% (32/164) of isolates, with equal distribution between regions and hosts. Only four isolates, two E. coli and two K. pneumoniae, showed phenotypic resistance: mcr-1 was present in both E. coli strains but absent in the K. pneumoniae strains. Conclusions. Despite a low prevalence of phenotypic resistance to colistin, the high prevalence of the mcr-1 gene in E. coli is of concern. Ecuador's ban on using colistin in animal husbandry must be enforced, and continual monitoring of the situation should be implemented. [ABSTRACT FROM AUTHOR]

A recent study analyzed the genotypes and virulence-associated genes of 46 ESBL-producing Escherichia coli (E. coli) strains isolated from the blood of patients with urinary tract infections (UTIs). The study aimed to understand the characteristics of UPEC strains associated with severe infections. The dominant multilocus sequence typing (MLST) was ST131, followed by ST73, ST95, and ST38, which are frequently observed in UPEC strains. The study found that the correlation between MLST and repertories of virulence-associated genes should be considered to understand UPEC virulence. [Extracted from the article]

A recent report from Semmelweis University in Budapest, Hungary, highlights the role of multidrug-resistant Klebsiella pneumoniae (MDR-KP) and its resistance plasmids in gastrointestinal colonization and host-defense. The study used a murine infection model to investigate the colonization of MDR-KP and Escherichia coli strains with resistance plasmids. The results showed that both the MDR-KP clone and the resistance plasmids contribute to the colonization rate in the gastrointestinal tract. The study suggests that these factors provide survival and colonization benefits in the gut. [Extracted from the article]

Researchers from Central South University in China have conducted a study on Klebsiella variicola, an opportunistic pathogen often misidentified as Klebsiella pneumoniae. The study aimed to examine the genomic properties and evolutionary relationships of clinical isolates of K. variicola. The researchers analyzed the genomic data of 70 K. variicola strains and found that drug resistance genes, particularly beta-lactamase and aminoglycoside, were highly prevalent. The study highlights the need for improved diagnostic tools and therapeutic strategies for K. variicola infections, as well as continued surveillance and monitoring of the strains for better understanding of the epidemiology and informing public health strategies. [Extracted from the article]

A recent study conducted in Jeonbuk, South Korea, focused on the production of 2,3-butanediol, a chemical used in various industries, from glycerol using the K. pneumoniae GEM167 strain. The researchers developed a modified strain of K. pneumoniae that had decreased production of competitive metabolites and increased production of 2,3-butanediol. They found that under specific culture conditions, this modified strain achieved the highest reported productivity of 2,3-butanediol from glycerol. The study also explored the correlation between oxygen transfer efficiency and 2,3-butanediol production. The research was supported by the Korea Research Institute of Bioscience and Biotechnology and the National Research Council for Economics, Humanities & Social Sciences. [Extracted from the article]

A recent study conducted at Nanchang University in Jiangxi, China has discovered that 3-hydroxy-2-butanone (acetoin) can be used as a volatile organic compound (VOC) biomarker for detecting carbapenemase-producing Klebsiella pneumoniae (K. pneumoniae). The researchers used gas chromatography-ion mobility spectrometry (GC-IMS) to detect acetoin released by K. pneumoniae during growth. They also investigated the impact of imipenem and carbapenemase inhibitors on acetoin emission. The findings suggest that acetoin has the potential to be a useful biomarker for detecting carbapenemase-producing K. pneumoniae. [Extracted from the article]

A recent study conducted by researchers from the State University of New York (SUNY) Albany has examined the population structure of Klebsiella pneumoniae, a pathogen associated with bloodstream infections. The study found that these infections are linked to adverse health complications and high mortality rates. The research also revealed the presence of antimicrobial resistance (AMR) in the population, limiting treatment options and exacerbating public health and clinical burdens. The study highlights the importance of understanding the genetic background of host strains and the routes of plasmid transmission in the spread of AMR in bloodstream infections. [Extracted from the article]

A study conducted at the First Hospital of Jilin University in China has found that Ginkgolic Acid (GA) can effectively inhibit the KPC-2 enzyme in Klebsiella pneumoniae, a type of bacteria that has developed resistance to carbapenem antibiotics. The researchers discovered that GA can enhance the killing effect of carbapenems on KPC-2-positive Klebsiella pneumoniae by binding to the active pocket of the enzyme. Additionally, GA was found to disrupt the integrity of the bacterial membrane, further increasing the bactericidal ability of carbapenems. This study suggests that GA could be a promising inhibitor of KPC-2 and improve the prognosis of patients with carbapenem-resistant infections. [Extracted from the article]

A study conducted by researchers at Majmaah University in Saudi Arabia focused on the prevalence and antimicrobial mechanism of carbapenem-resistant Klebsiella pneumoniae (CRKP). The study found that CRKP poses a serious threat to public health, as carbapenems are often used as a last resort to treat K. pneumoniae infections. The researchers collected samples from various clinical specimens and isolated K. pneumoniae strains. The strains exhibited multi-drug resistance and were non-susceptible to several antibiotics. The study emphasizes the need for continuous monitoring of drug-resistance genes to inform policy decisions. [Extracted from the article]

Researchers from the University of Sonora in Mexico have conducted a study on a multidrug-resistant strain of Klebsiella pneumoniae, a Gram-negative bacteria. The strain, UABC-Str0120, was isolated from a urine sample of a patient with a community-acquired urinary tract infection. Whole-genome sequencing revealed that the strain exhibited resistance to various antibiotics and harbored multiple virulence genes and mobile genetic elements. The researchers concluded that this strain poses a significant threat to both immunocompromised and healthy individuals in community settings. The study was supported by the Consejo Nacional de Ciencia y Tecnologia (CONACyT). [Extracted from the article]

A recent study conducted by researchers at the University of Anbar has identified bacteria and fungi associated with mastitis in breastfeeding women. Mastitis is a common infection that occurs when bacteria enter the breast tissue through breaks in the skin. The study found that Staphylococcus aureus, Klebsiella pneumoniae, and Candida spp. were the most prevalent bacteria linked to mastitis. The presence of redness was observed as a significant sign in cases associated with Candida tropicalis. This research provides valuable insights into the microbial diversity of mastitis in breastfeeding women. [Extracted from the article]

A systematic review and meta-analysis conducted by researchers at Woldia University aimed to determine the prevalence of carbapenem-resistant gram-negative bacteria among African newborns suspected of having sepsis. The study analyzed 36 studies and found that the pooled prevalence of carbapenem resistance in Africa was 30.34%. The research concluded that urgent antimicrobial stewardship practices, strengthened surveillance systems, and effective treatment for neonates with sepsis are needed, as there was significant variation in resistance across the continent. [Extracted from the article]

A new report from An-Najah National University discusses the characterization of multidrug-resistant Enterobacterales (MDR-E) isolated from clinical samples in the West Bank, Palestine. The study found that 47.83% of the isolates were extended-spectrum beta-lactamase producers (ESBLE), and 17% were carbapenem-resistant Enterobacterales (CRE) isolates. The most prevalent species were K. pneumoniae and E. coli. The research highlights the high burden of MDR-E infections in Palestine and emphasizes the importance of surveillance and monitoring of antimicrobial-resistant infections. [Extracted from the article]

A study conducted at the Zuyderland Medical Center in the Netherlands focused on tracing the origin of carbapenemase-producing Pseudomonas aeruginosa (CPPA), a bacteria that can cause fatal infections in hospitals. The study found that a repatriated patient from Kenya who carried NDM-1-producing CPPA introduced an extensively drug-resistant subclone of P. aeruginosa ST357 to the Netherlands. The research suggests that monitoring repatriated patients for CPPA and being vigilant about environmental contamination can help detect and prevent further dissemination of the bacteria. The study provides valuable insights into the transmission routes and resistance patterns of CPPA. [Extracted from the article]

A recent study conducted by the University of Concepcion in Chile has examined the molecular epidemiology of carbapenem-resistant Pseudomonas aeruginosa (CRPA) isolates in Chilean hospitals. The study found that the ST654 high-risk clone was the most predominant lineage among the CRPA isolates analyzed. These isolates exhibited a broad resistome and were associated with the O4-serotype. The study highlights the importance of molecular surveillance of CRPA in Chile and suggests that this lineage is undergoing a divergent evolutionary path in the country. [Extracted from the article]

A study conducted at Gachon University in South Korea analyzed blood culture data from 2016 to 2020 to determine the distribution of bacteria and antibiotic resistance patterns. The most commonly isolated bacterium from blood cultures was Escherichia coli, followed by Klebsiella pneumoniae and Staphylococcus aureus. The study found that the resistance rates of certain antibiotics, such as ciprofloxacin and imipenem, increased over the study period for some bacteria. The research highlights the importance of consistently collecting and analyzing blood culture results to inform antibiotic treatment decisions. [Extracted from the article]

A study conducted at Saurashtra University in Gujarat, India, has investigated the synthesis and antimicrobial activity of quinoxaline-based oxazole derivatives. The compounds showed significant antimicrobial activity against both Gram-negative and Gram-positive bacteria, suggesting their potential as therapeutic agents for bacterial infections. The research highlights the importance of exploring novel synthetic approaches and chemical structures in the development of antimicrobial agents. Further investigation is needed to determine their clinical application. This study was supported by the Department of Chemistry at Saurashtra University. [Extracted from the article]

A report from Beijing, China discusses the emergence of Extended-spectrum b-lactamase producing Enterobacteriaceae (ESBL-E) in veterinary hospitals and its impact on public health. The study collected samples from a veterinary hospital in Chengdu, China, including animals, healthcare workers, and the environment. The results showed that 34.7% of the samples tested positive for ESBL-E, with the most prevalent strains being ESBL-E.coli and ESBL-Kp. The study emphasizes the need for interdisciplinary investigation and cooperation to limit the transmission of high-risk strains and implement effective public health interventions. [Extracted from the article]

A recent report from Government College University in Faisalabad, Pakistan, explores the correlation between virulence and antimicrobial resistance in Klebsiella pneumoniae. Klebsiella pneumoniae is responsible for a wide range of infections, including pneumonia, urinary tract infections, liver abscesses, and bacteremia. The study highlights the emergence of hypervirulent strains and multidrug-resistant isolates of K. pneumoniae, which pose a threat to treatment. The interplay between resistance and virulence in this pathogen is still poorly understood, and further research is needed to shed light on this topic. [Extracted from the article]

A study conducted by researchers at Kurdistan University of Medical Sciences in Sanandaj, Iran, examined the prevalence of resistance to fluoroquinolones in Extended-Spectrum Beta-Lactamase (ESBL)-producing Klebsiella pneumoniae isolates in health centers in 2018. The study found that 52.23% of the isolates were resistant to ciprofloxacin and levofloxacin, and 37.31% were identified as ESBL. The researchers concluded that the simultaneous resistance to fluoroquinolones and ESBL production in Klebsiella pneumoniae isolates can limit treatment options and pose a challenge for medical centers. [Extracted from the article]

This document is a patent application for a method of producing Klebsiella pneumoniae O-antigens in Escherichia coli (E. coli) host cells. The patent application describes the specific gene clusters and nucleotide sequences involved in encoding the O-antigens, as well as the use of vectors and primers in the process. The invention aims to provide a more efficient and cost-effective method for producing these antigens, which are important for immunological research and vaccine development. The patent application includes various claims and additional information can be found in the full patent document. [Extracted from the article]

A recent study conducted by researchers at Can Tho University in Vietnam examined the antibiotic resistance of Klebsiella pneumoniae (K. pneumoniae) and carbapenemase-producing Klebsiella pneumoniae (CPKP) strains in Can Tho, Vietnam. The study found that CPKP accounted for 31.9% of all K. pneumoniae infections and exhibited significant resistance to various antibiotics, including penicillin, cefazolin, ciprofloxacin, ceftriaxone, and ceftazidime. However, amikacin, gentamicin, and TMP/SMX were shown to be effective in treating patients infected with CPKP strains. This research provides valuable insights into the situation of antibiotic resistance in K. pneumoniae in Vietnam. [Extracted from the article]

The article focuses on comparing the effectiveness of ceftazidime-avibactam (CZA) combination therapy versus monotherapy for treating pneumonia caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). Topics include the clinical and microbiological outcomes of CZA combination therapy, the impact on 14-day and 30-day mortality rates, and the role of carbapenems in enhancing treatment efficacy.

Researchers from Tanta University have conducted a study on enzymes and coenzymes, specifically focusing on b-lactam resistance, which is a global public health concern. The researchers aimed to evaluate the potential use of galloylquinic acid (GQA) as a b-lactamase inhibitor. They cloned and expressed genes encoding for serine b-lactamases and found that GQA significantly reduced the minimum inhibitory concentrations (MICs) of b-lactam antibiotics, making them more effective against resistant strains. The study suggests that GQA has promising potential as a lead molecule for the development of more potent b-lactamase inhibitors. [Extracted from the article]

Researchers at the Capital Institute of Pediatrics in Beijing, China have developed a rapid and sensitive diagnostic tool for detecting Mycoplasma pneumoniae, a pathogen responsible for community-acquired pneumonia, especially in children and adolescents. The method combines multiple cross displacement amplification (MCDA) with real-time fluorescence technology. The assay accurately identifies M. pneumoniae strains without cross-reacting with other bacteria and can be completed within 1 hour, making it a potential point-of-care testing tool for resource-limited regions. The study was published in Frontiers in Cellular and Infection Microbiology. [Extracted from the article]

A recent study conducted at Malla Reddy Medical College for Women in Telangana, India, has reported findings on Klebsiella pneumoniae. The study focuses on a case of acute-onset postoperative endophthalmitis caused by multidrug-resistant Klebsiella pneumoniae following vitrectomy for malignant glaucoma. The patient initially underwent cataract surgery but later developed malignant glaucoma and subsequently endophthalmitis. The researchers were able to successfully treat the patient with timely intervention, resulting in a reasonably good visual recovery. This case report highlights the importance of prompt and appropriate treatment in managing such complications. [Extracted from the article]

A study conducted at the University of Technology Baghdad in Iraq has explored the potential of biosynthesized graphene oxide nanoparticles (GONPs) for biomedical applications. The researchers used an environmental method to produce GONPs and tested their antimicrobial properties against Klebsiella pneumoniae and Bacillus cereus. The GONPs exhibited significant growth inhibition against both bacterial strains, with the highest anti-biofilm activity observed against Bacillus cereus. Additionally, the GONPs showed promising cytotoxicity against lung cancer cells and demonstrated strong antioxidant properties. The study suggests that laser production of GONPs could be a simpler and safer method for producing high-purity nanoparticles for future cancer therapies. [Extracted from the article]

A recent study conducted at the Vellore Institute of Technology in India examined the antimicrobial resistance patterns of Klebsiella pneumoniae strains responsible for neonatal sepsis. The researchers found high levels of resistance to beta-lactam and fluoroquinolone antibiotics in these strains. Molecular docking analysis revealed reduced binding of beta-lactams to penicillin-binding proteins and increased affinity for beta-lactamases, contributing to decreased effectiveness. The study highlights the urgent need for the development of alternative therapies to address the rising antimicrobial resistance in neonatal sepsis. [Extracted from the article]

A recent study conducted by researchers at the Consejo Superior de Investigaciones Cientificas in Madrid, Spain, focused on Klebsiella pneumoniae, an opportunistic bacterium that can cause severe infections in immunocompromised individuals. The study examined the surface sugar epitopes of different clinical isolates of K. pneumoniae and their recognition by lectins of the innate immune system. The researchers found that there were significant differences in the recognition of galactose- and mannose-specific lectins, suggesting that the O-chain of the bacterium may be the ligand. The study also revealed that Siglecs and galectins target different structures on the surface of K. pneumoniae, making them non-redundant tools of the innate immune system. [Extracted from the article]

A recent report from Dokkyo Medical University in Japan highlights the detection of Klebsiella pneumoniae subsp. ozaenae (K. ozaenae) as the cause of bacterial meningitis in Japan for the first time. While community-acquired infections caused by K. ozaenae are rare, they are often found in sputum specimens. The study emphasizes the importance of using additional detection methods, such as mass spectrometry, to correctly identify Klebsiella pneumoniae in such cases. This research provides valuable insights into the epidemiology and identification of K. ozaenae infections. [Extracted from the article]

A recent study conducted by researchers at Federal University in Dourados, Brazil, explored the antimicrobial potential of 560 compounds from the Pandemic Response Box and COVID Box against resistant gram-negative bacteria. The study found that several compounds exhibited significant reductions in biofilm formation and growth in Klebsiella pneumoniae, while trimethoprim showed potential against Serratia marcescens. The researchers concluded that these findings highlight the potency of existing antibiotics and novel compounds in combating multidrug-resistant strains of bacteria, emphasizing the importance of reconsidering known antibiotics and utilizing drug repositioning strategies to address the increasing risk of antimicrobial resistance. [Extracted from the article]

Researchers from the National Research Centre in Egypt have conducted a study on the medicinal properties of Astragalus caprinus, a plant found in Egypt and the Arab world. The study analyzed the bioactive chemicals present in the plant and tested its antimicrobial activity against various pathogens. The researchers found that Astragalus caprinus has potential therapeutic effects and could be used to prevent disease complications. The findings suggest that this plant could be utilized as a natural source for producing health-boosting products in developing countries. [Extracted from the article]

A study conducted at the University Hospital of Campania in Naples, Italy, examined the epidemiological and microbiological aspects of aerobic vaginitis in female patients over a five-year period. The most common strains found were E. coli, Citrobacter spp., E. faecalis, S. haemolitycus, and Candida albicans. The study also analyzed the susceptibility patterns of gram-negative and gram-positive bacterial isolates and found that certain antibiotics were more effective against each type. The researchers concluded that integrating proper microbiological cultures into clinical practice and implementing nationwide surveillance guidelines are necessary to improve the management of aerobic vaginitis and combat antimicrobial resistance. [Extracted from the article]

A recent study conducted by the Department of Microbiology in Cambridge, Massachusetts, explores the persistence and enrichment of multidrug-resistant Klebsiella bacteria in oral and nasal communities during long-term starvation. The research suggests that the oral and nasal cavities can serve as reservoirs for opportunistic pathogens, including Klebsiella, which can asymptomatically colonize these areas and possess antibiotic resistance genes. The study found that under starvation conditions, the bacterial community composition in the oral and nasal cavities shifted dramatically and became enriched in Klebsiella species. This enrichment may be due to Klebsiella's ability to outcompete other members of the microbiome. The findings highlight the importance of understanding the transmission factors and persistence of Klebsiella in both healthy and diseased individuals. [Extracted from the article]

A recent study conducted at the University of Baghdad in Iraq focused on Klebsiella pneumoniae, a bacterium associated with hospital-acquired infections. The researchers aimed to detect the presence of two virulence-associated genes, fim H and UDP, in multiple drug-resistant K. pneumoniae isolates. They collected 90 isolates from various clinical samples and found that the isolates were highly resistant to vancomycin but had a lower resistance rate to colistin. The study also revealed a high prevalence of the virulence genes fim H and UDP among the drug-resistant isolates. The researchers concluded that multidrug-resistant isolates were associated with the presence of these virulence genes. [Extracted from the article]

A study conducted by the Department of Microbiology aimed to assess the prevalence of extended-spectrum beta-lactamase (ESBL) and carbapenemase producing Klebsiella pneumoniae in patients with suspected urinary tract infections (UTIs). The study found that out of 880 urine samples collected, 9.30% showed significant growth, with a higher prevalence of UTIs in male patients. The isolates of K. pneumoniae showed resistance to various antibiotics, with multi-drug resistance found in 54.83% of cases. Colistin was found to be the most effective drug against these strains. Early detection of ESBL and carbapenemase-producing isolates is crucial for reducing mortality rates and preventing the spread of these strains within hospitals. [Extracted from the article]

A recent study conducted by researchers at Shanxi Medical University focused on Klebsiella pneumoniae, a type of bacteria. The study specifically examined a case of primary mesenteric abscess caused by Klebsiella pneumoniae, which is a rare abdominal infection. The researchers emphasized the importance of timely diagnosis and treatment, including the use of computerized tomography for diagnosis, surgical intervention, antibiotics, and nutritional support. The study concluded that successful therapy for primary mesenteric abscess requires factors such as adequate postoperative drainage, appropriate antibiotic use based on bacterial culture, early ambulation after surgery, and sufficient nutritional support. [Extracted from the article]

A new report from researchers at Kuala Lumpur Hospital discusses a case of an unusual syndrome involving Klebsiella pneumoniae, a type of bacteria, that caused liver abscess, gallbladder empyema, and infective endocarditis in a 60-year-old woman with diabetes. The patient experienced symptoms such as fever, pain, and vomiting, and was found to have a collection within the liver and a distended gallbladder. Treatment with antibiotics and drainage resulted in resolution of the infections. The researchers emphasize the importance of considering the possibility of concomitant infective endocarditis in patients with Klebsiella pneumoniae liver abscesses, despite its rarity, to avoid potential complications. [Extracted from the article]

A preprint abstract from biorxiv.org discusses the development of an engineered prodrug called AcephPT that selectively suppresses beta-lactam resistant bacteria. The prodrug exploits beta-lactamase activity to target and suppress bacteria producing extended-spectrum-beta-lactamases (ESBLs), while avoiding interaction with penicillin-binding proteins. The study demonstrates that AcephPT effectively suppresses ESBL-producing bacteria in both clonal populations and mixed microbial cultures, while promoting the growth of beta-lactamase-non-producing bacteria. This research shows promise in combating beta-lactam resistance and promoting antimicrobial stewardship. However, it is important to note that this preprint has not yet undergone peer review. [Extracted from the article]